Selective self-synchronization of pulses in neuronal networks of the visual system

In the present study we have checked the hypothesis that the degree of pulse synchrony in neuronal pools is determined by the level of excitation of the neuronal network or its loci and that this relationship does not depend on the factor that causes the excitation. Pulse reactions of neurons in pools (2–4 cells) of cat lateral geniculate nucleus and visual cortex were registered. Neurons were excited using either visual stimuli or glutamic acid microinjections into neuronal pools. The increase of neural pool excitation level (No) regardless of the type of stimulus was shown to increase the pulse synchrony (Ns), with a correlation coefficient of 0.716 ± 0.217. One may suppose that the level of neuronal network excitation “governs” the synchrony of pulses generated by the network, i.e., neuronal networks function in compliance with the principle of self-synchronization.     

Midbrain activity shapes high-level visual properties in the primate temporal cortex

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Silver coelacanths from Spain are not proofs of a Pre-scientific Discovery

In 1964 and 1965, two silver fish pendants depicting coelacanths and thought to be religious votive from Spanish churches were purchased on the art market in Spain, dated between the 17th and late 19th century, long before the discovery for science of the living coelacanth in 1938. It was speculated that they originated either from the Mediterranean, subtropical Atlantic, or subtropical Pacific (de Sylva 1966, Bruton 1985, Anonymous 1993, Greenwell 1994, Raynold & Mangiacopra 1995). Some authors believe that the silver fish pendants represent a new species of coelacanthiforms (Raynold & Mangiacopra 1995), others claimed the pendants to be only a wishful fantasy of scientists and not coelacanths at all (Thomson 1991). However, new studies revealed that the silver fish artefacts are indeed coelacanths but were in fact produced more recently with the Comorian coelacanth, Latimeria chalumnae, as a model.